Cooling fan with curved V-shaped impellers

Abstract

A cooling fan includes a rotatable hub and a plurality of generally V-shaped impellers that are angularly displaced from each other and that extend outwardly from the hub. Each of the impellers has first and second impeller halves that extend outwardly from the hub and that are connected to each other so as to form cooperatively an angle therebetween.

I claim:  
     
       1. A cooling fan comprising: 
       a rotatable hub; and  
       a plurality of generally V-shaped impellers that are angularly displaced from each other and that extend outwardly from said hub, each of said impellers having first and second impeller halves that extend outwardly from said hub and that are connected to each other so as to form cooperatively an angle therebetween, wherein each of the said impellers has a root connected to said hub, and a tip opposite to said root, said first impeller half having a first leading edge extending outwardly from said root to said tip, and a first trailing edge opposite to said first leading edge and extending outwardly from said root to said tip, said second impeller half having a second leading edge extending outwardly from said root to said tip and spaced apart from and substantially flush with said first leading edge in an axial direction relative to said hub, and a second trailing edge extending outwardly from said root to said tip and connected to said first trailing edge to form said angle.  
     
     
       2. A cooling fan comprising: 
       a rotatable hub; and  
       a plurality of generally V-shaped impellers that are angularly displaced from each other and that extend outwardly from said hub, each of said impellers having first and second impeller halves that extend outwardly from said hub and that are connected to each other so as to form cooperatively an angle therebetween, wherein each of the said impellers has a root connected to said hub, and a tip opposite to said root, said first impeller half having a first leading edge extending curvedly and outwardly from said root to said tip, and a first trailing edge opposite to said first leading edge and extending curvedly and outwardly from said root to said tip, said second impeller half having a second leading edge extending curvedly and outwardly from said root to said tip and spaced apart from and substantially flush with said first leading edge in an axial direction relative to said hub, and a second trailing edge extending curvedly and outwardly from said root to said tip and connected to said first trailing edge to form said angle.  
     
     
       3. The cooling fan of  claim 2 , wherein said hub includes first and second hub halves, said cooling fan further comprising an interlocking member that includes a plurality of grooves which are formed in said first hub half, and a plurality of tongues which are formed on said second hub half, said tongues engaging respectively said grooves so as to secure said first and second hub halves together, said first impeller halves of said impellers being connected to and extending outwardly from said first hub half, said second impeller halves of said impellers being connected to and extending outwardly from said second hub half. 
     
     
       4. The cooling fan of  claim 3 , wherein said first hub half and said first impeller halves of said impellers are made from a plastic material and are integrally formed by molding, said second hub half and said second impeller halves of said impellers being made from said plastic material and being integrally formed by molding, said first trailing edge of each of said first impeller halves being integrally connected to said second trailing edge of a respective one of said second impeller halves by high frequency welding.